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Hubertus Fischer - One of the best experts on this subject based on the ideXlab platform.
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Limited Retreat of the Wilkes Basin Ice Sheet During the Last Interglacial
Geophysical Research Letters, 2020Co-Authors: Johannes Sutter, Olaf Eisen, Martin Werner, Klaus Grosfeld, Thomas Kleiner, Hubertus FischerAbstract:The response of the East Antarctic Ice Sheet to global warming represents a major source of uncertainty in sea level projections. Thinning of the East Antarctic George V and Sabrina Coast ice‐cover is currently taking place, and regional ice‐sheet instability episodes might have been triggered in past warm climates. However, the magnitude of ice retreat in the past can not yet be quantitatively derived from paleo‐proxy records alone. We propose that a runaway retreat of the George V coast grounding line and subsequent instability of the Wilkes Basin ice‐sheet would either leave a clear imprint on the water isotope composition in the Talos Dome region or prohibit a Talos Dome ice‐core record from the Last Interglacial altogether. Testing this hypothesis our ice sheet model simulations suggest, that Wilkes Basin ice‐sheet retreat remained relatively limited during the Last Interglacial and provide a constraint on Last Interglacial East Antarctic grounding line stability.
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Limited Retreat of the Wilkes Basin Ice Sheet during the Last Interglacial.
2020Co-Authors: Johannes Sutter, Olaf Eisen, Martin Werner, Klaus Grosfeld, Thomas Kleiner, Hubertus FischerAbstract:<p>The response of the marine sectors of the East Antarctic Ice Sheet to future global warming represents a major source of uncertainty in sea level projections. If greenhouse gas emissions continue unbridled, ice loss in these areas may contribute up to several meters to long-term global sea level rise. In East Antarctica, thinning of the ice cover of the George V and Sabrina Coast is currently taking place, and its destabilization in past warm climate periods has been implied. The extent of such past Interglacial retreat episodes cannot yet be quantitatively derived from paleo proxy records alone. Ice sheet modelling constrained by paleo observations is therefore critical to assess the stability of the East Antarctic Ice Sheet during warmer climates. We propose that a runaway retreat during the Last Interglacial of the George V Coast grounding line into the Wilkes Subglacial Basin would either leave a clear imprint on the water isotope composition in the neighbouring Talos Dome ice-core record or prohibit the preservation of an ice core record from the Last Interglacial alltogether. We test this hypothesis using a dynamic ice sheet model and infer that the marine Wilkes Basin ice sheet remained stable throughout the Last Interglacial (130,000-120,000 years ago). Our analysis provides the first constraint on Last Interglacial East Antarctic grounding line stability by benchmarking ice sheet model simulations with ice core records. Our findings also imply that ambitious mitigation efforts keeping global temperature rise in check could safeguard this region from irreversible ice loss in the long term.</p>
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High-resolution record of Northern Hemisphere climate extending into the Last Interglacial period.
Nature, 2004Co-Authors: Katrine Krogh Andersen, Nobuhiko Azuma, Jean-marc Barnola, M. Bigler, Pierre E. Biscaye, Nicolas Caillon, Jérôme Chappellaz, H. B. Clausen, Dorthe Dahl-jensen, Hubertus FischerAbstract:High-resolution record of Northern Hemisphere climate extending into the Last Interglacial period
Mark J. Sier - One of the best experts on this subject based on the ideXlab platform.
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The diachronous Eemian (Last Interglacial) in Europe
2014Co-Authors: Mark J. Sier, J. Peeters, Kim M. Cohen, Mark J. Dekkers, Josep M. Parés, Wil RoebroeksAbstract:The Eemian, first defined by Harting in 1874 in the Netherlands, is the term for the terrestrial Last Interglacial in Europe. Extensive research has been devoted to this period from a wide range of disciplines. Archaeologists have an interested in this period as it contains the Last Interglacial presence of Homo neanderthalensis in Europe. Understanding the geographic and environmental range of this species, particularly the range limits, gives important insights in their social and/ or technological abilities. Studying the North western European (including the Eemian typelocality in the Netherlands) Eemian helps to contribute to this understanding. Here we present the combined results of research done at three Eemian sites, Neumark Nord 2 (Germany), Caours (France) and Rutten (Netherlands). Detailed palaeomagnetic and palaeoenvironmental studies were performed at these sites. In all three sites we indentified a palaeomagnetic excursion which is the Blake Event. We used this Blake Event as a chronostratigraphic marker in order to compare our records with the well dated marine core MD952042 (of the Iberian coast). When comparing our results with this core we can conclude that the onset of Eemian was delayed by 5000 years in north western Europe with respect to southern Europe. This means that the onset of the Eemian in north western Europe is placed well after the Marine Isotope Stage 5e sealevel highstand. As a result no “dry path” towards Great Britain was available during this warm period, possibly explaining the absence of Homo neanderthalensis during this period.
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Direct terrestrial–marine correlation demonstrates surprisingly late onset of the Last Interglacial in central Europe
Quaternary research, 2011Co-Authors: Mark J. Sier, Mark J. Dekkers, Wil Roebroeks, Corrie Bakels, Enrico Brühl, Dimitri De Loecker, Sabine Gaudzinski-windheuser, Norbert Hesse, Adam Jagich, Lutz KindlerAbstract:An interdisciplinary study of a small sedimentary basin at Neumark Nord 2 (NN2), Germany, has yielded a high-resolution record of the palaeomagnetic Blake Event, which we are able to place at the early part of the Last Interglacial pollen sequence documented from the same section. We use this data to calculate the duration of this stratigraphically important event at 3400 ± 350 yr. More importantly, the Neumark Nord 2 data enables precise terrestrial–marine correlation for the Eemian stage in central Europe. This shows a remarkably large time lag of ca. 5000 yr between the MIS 5e ‘peak’ in the marine record and the start of the Last Interglacial in this region.
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direct terrestrial marine correlation demonstrates surprisingly late onset of the Last Interglacial in central europe
Quaternary Research, 2011Co-Authors: Mark J. Sier, Mark J. Dekkers, Wil Roebroeks, Corrie Bakels, Enrico Brühl, Dimitri De Loecker, Norbert Hesse, Sabine Gaudzinskiwindheuser, Adam JagichAbstract:An interdisciplinary study of a small sedimentary basin at Neumark Nord 2 (NN2), Germany, has yielded a high-resolution record of the palaeomagnetic Blake Event, which we are able to place at the early part of the Last Interglacial pollen sequence documented from the same section. We use this data to calculate the duration of this stratigraphically important event at 3400 ± 350 yr. More importantly, the Neumark Nord 2 data enables precise terrestrial–marine correlation for the Eemian stage in central Europe. This shows a remarkably large time lag of ca. 5000 yr between the MIS 5e ‘peak’ in the marine record and the start of the Last Interglacial in this region.
Adam Jagich - One of the best experts on this subject based on the ideXlab platform.
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Direct terrestrial–marine correlation demonstrates surprisingly late onset of the Last Interglacial in central Europe
Quaternary research, 2011Co-Authors: Mark J. Sier, Mark J. Dekkers, Wil Roebroeks, Corrie Bakels, Enrico Brühl, Dimitri De Loecker, Sabine Gaudzinski-windheuser, Norbert Hesse, Adam Jagich, Lutz KindlerAbstract:An interdisciplinary study of a small sedimentary basin at Neumark Nord 2 (NN2), Germany, has yielded a high-resolution record of the palaeomagnetic Blake Event, which we are able to place at the early part of the Last Interglacial pollen sequence documented from the same section. We use this data to calculate the duration of this stratigraphically important event at 3400 ± 350 yr. More importantly, the Neumark Nord 2 data enables precise terrestrial–marine correlation for the Eemian stage in central Europe. This shows a remarkably large time lag of ca. 5000 yr between the MIS 5e ‘peak’ in the marine record and the start of the Last Interglacial in this region.
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direct terrestrial marine correlation demonstrates surprisingly late onset of the Last Interglacial in central europe
Quaternary Research, 2011Co-Authors: Mark J. Sier, Mark J. Dekkers, Wil Roebroeks, Corrie Bakels, Enrico Brühl, Dimitri De Loecker, Norbert Hesse, Sabine Gaudzinskiwindheuser, Adam JagichAbstract:An interdisciplinary study of a small sedimentary basin at Neumark Nord 2 (NN2), Germany, has yielded a high-resolution record of the palaeomagnetic Blake Event, which we are able to place at the early part of the Last Interglacial pollen sequence documented from the same section. We use this data to calculate the duration of this stratigraphically important event at 3400 ± 350 yr. More importantly, the Neumark Nord 2 data enables precise terrestrial–marine correlation for the Eemian stage in central Europe. This shows a remarkably large time lag of ca. 5000 yr between the MIS 5e ‘peak’ in the marine record and the start of the Last Interglacial in this region.
George Kukla - One of the best experts on this subject based on the ideXlab platform.
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Last Interglacial climates
Quaternary Research, 2002Co-Authors: George Kukla, Jacques-louis De Beaulieu, J. Gavin, Michael L Bender, Gerard C Bond, Wallace S Broecker, P Cleveringa, Timothy D Herbert, John Imbrie, Jean JouzelAbstract:The Last Interglacial, commonly understood as an interval with climate as warm or warmer than today, is represented by marine isotope stage (MIS) 5e, which is a proxy record of low global ice volume and high sea level. It is arbitrarily dated to begin at approximately 130,000 yr B.P. and end at 116,000 yr B.P. with the onset of the early glacial unit MIS 5d. The age of the stage is determined by correlation to uranium–thorium dates of raised coral reefs. The most detailed proxy record of Interglacial climate is found in the Vostok ice core where the temperature reached current levels 132,000 yr ago and continued rising for another two millennia. Approximately 127,000 yr ago the Eemian mixed forests were established in Europe. They developed through a characteristic succession of tree species, probably surviving well into the early glacial stage in southern parts of Europe. After ca. 115,000 yr ago, open vegetation replaced forests in northwestern Europe and the proportion of conifers increased significantly farther south. Air temperature at Vostok dropped sharply. Pulses of cold water affected the northern North Atlantic already in late MIS 5e, but the central North Atlantic remained warm throughout most of MIS 5d. Model results show that the sea surface in the eastern tropical Pacific warmed when the ice grew and sea level dropped. The essentially Interglacial conditions in southwestern Europe remained unaffected by ice buildup until late MIS 5d when the forests disappeared abruptly and cold water invaded the central North Atlantic ca. 107,000 yr ago.
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Last Interglacial and Early Glacial ENSO
Quaternary Research, 2002Co-Authors: George Kukla, Amy C. Clement, Mark A. Cane, J. Gavin, Stephen E. ZebiakAbstract:Although the link between insolation and climate is commonly thought to be in the high northern latitudes in summer, our results show that the start of the Last glaciation in marine isotope stage (MIS) 5d was associated with a change of insolation during the transitional seasons in the low latitudes. A simplified coupled ocean-atmosphere model shows that changes in the seasonal cycle of insolation could have altered El Nino Southern Oscillation (ENSO) variability so that there were almost twice as many warm ENSO events in the early glacial than in the Last Interglacial. This indicates that ice buildup in the cooled high latitudes could have been accelerated by a warmed tropical Pacific.
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The Last Interglacial
Science, 2000Co-Authors: George KuklaAbstract:Climate during the Last 10,000 years, the Holocene, has been relatively mild and stable. In contrast, the climate during the Last Interglacial is often portrayed as more variable. But, as Kukla discusses in this Perspective, evidence for a more stable Last Interglacial is emerging. Furthermore, the transition to the next glacial proceeded in stages and was not uniform across Europe.
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How long and how stable was the Last Interglacial
Quaternary Science Reviews, 1997Co-Authors: George Kukla, Jerry F. Mcmanus, Denis-didier Rousseau, Isabelle ChuineAbstract:Abstract Surface ocean indicators in the North Atlantic during marine isotope stage (MIS) 5 correlate closely with the vegetational succession in northeastern France. The Melisey I silty layer, which marks the end of the Last Interglacial biozone in La Grande Pile pollen record, appears coeval with the polar front advance C24 registered in the core V29-191 by a sharply increased presence of ice-rafted detritus and the cold water foraminifer Neogloboquadrina pachyderma sinistral . Since this event is younger than the peak of MIS 5d, the Last Interglacial, as recognized in northern France, correlates not only with the MIS 5e, but also with a substantial part of MIS 5d. The Last Interglacial in La Grande Pile was twice as long as the Holocene and the climate in its first half was apparently not less stable than during the current Interglacial. If the future natural climates were to develop as analogs of the past, then the onset of the next glacial environments on land would be still many millennia ahead.
Eelco J. Rohling - One of the best experts on this subject based on the ideXlab platform.
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Asynchronous Antarctic and Greenland ice-volume contributions to the Last Interglacial sea-level highstand
Nature communications, 2019Co-Authors: Eelco J. Rohling, Fiona Hibbert, Katharine M Grant, Eirik Vinje Galaasen, Nil Irvali, Helga F Kleiven, Gianluca Marino, Ulysses S Ninnemann, Andrew P. Roberts, Yair RosenthalAbstract:The Last Interglacial (LIG; ~130 to ~118 thousand years ago, ka) was the Last time global sea level rose well above the present level. Greenland Ice Sheet (GrIS) contributions were insufficient to explain the highstand, so that substantial Antarctic Ice Sheet (AIS) reduction is implied. However, the nature and drivers of GrIS and AIS reductions remain enigmatic, even though they may be critical for understanding future sea-level rise. Here we complement existing records with new data, and reveal that the LIG contained an AIS-derived highstand from ~129.5 to ~125 ka, a lowstand centred on 125–124 ka, and joint AIS + GrIS contributions from ~123.5 to ~118 ka. Moreover, a dual substructure within the first highstand suggests temporal variability in the AIS contributions. Implied rates of sea-level rise are high (up to several meters per century; m c−1), and lend credibility to high rates inferred by ice modelling under certain ice-shelf instability parameterisations. The relative contributions of the Greenland and Antarctic Ice Sheets to Last Interglacial sea level rise remain debated, as do the timing and magnitude. Here, data show that the Antarctic Ice Sheet dominated particularly high levels of sea-level rise during the early Last Interglacial.
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Bipolar seesaw control on Last Interglacial sea level.
Nature, 2015Co-Authors: Gianluca Marino, Eelco J. Rohling, Katharine M Grant, Andrew P. Roberts, Laura Rodríguez-sanz, David Heslop, J D StanfordAbstract:Our current understanding of ocean–atmosphere–cryosphere interactions at ice-age terminations relies largely on assessments of the most recent (Last) glacial–Interglacial transition1, 2, 3, Termination I (T-I). But the extent to which T-I is representative of previous terminations remains unclear. Testing the consistency of termination processes requires comparison of time series of critical climate parameters with detailed absolute and relative age control. However, such age control has been lacking for even the penultimate glacial termination (T-II), which culminated in a sea-level highstand during the Last Interglacial period that was several metres above present4. Here we show that Heinrich Stadial 11 (HS11), a prominent North Atlantic cold episode5, 6, occurred between 135 ± 1 and 130 ± 2 thousand years ago and was linked with rapid sea-level rise during T-II. Our conclusions are based on new and existing6, 7, 8, 9 data for T-II and the Last Interglacial that we collate onto a single, radiometrically constrained chronology. The HS11 cold episode5, 6 punctuated T-II and coincided directly with a major deglacial meltwater pulse, which predominantly entered the North Atlantic Ocean and accounted for about 70 per cent of the glacial–Interglacial sea-level rise8, 9. We conclude that, possibly in response to stronger insolation and CO2 forcing earlier in T-II, the relationship between climate and ice-volume changes differed fundamentally from that of T-I. In T-I, the major sea-level rise clearly post-dates3, 10, 11 Heinrich Stadial 1. We also find that HS11 coincided with sustained Antarctic warming, probably through a bipolar seesaw temperature response12, and propose that this heat gain at high southern latitudes promoted Antarctic ice-sheet melting that fuelled the Last Interglacial sea-level peak.
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High rates of sea-level rise during the Last Interglacial period
Nature Geoscience, 2007Co-Authors: Eelco J. Rohling, Katharine M Grant, Ch. Hemleben, M. Siddall, Babette A A Hoogakker, M Bolshaw, Michal KuceraAbstract:Sea level during the Last Interglacial stood at least 4 m higher than at present, with evidence of short-term fluctuations of up to 10 m. A new continuous sea level record from the Red Sea and coral ages suggest that during these fluctuations, sea level changes were on the order of 1.6 m per century.
